[英國《國際飛行》近期報導]目前，美國普拉特·惠特尼公司正在實驗的一種先進的脈衝爆震發動機(PDE)距離實用性驗證已經指日可待。因為這種發動機可以瞬態加速/減速，所以它的潛在用途包括超音速無人戰鬥機、超音速攻擊飛彈、渦扇和涵道爆震燃燒混合的單級入軌動力裝置。
　　
　　目前，在美國海軍一項為期三年的風險減少計劃下，該PDE設計正在美國加利福尼亞中國湖的海軍航空武器中心進行最後階段的測試。普拉特·惠特尼公司領導的研究小組包括波音公司幻象工作組和聯合技術研究中心，該研究小組的工作重點是對一種概念上接近未來美國海軍超音速攻擊飛彈發動機、由5個爆震管組成的PDE設計進行測試。
　　
　　在工作過程中，PDE透過不斷向一個一端開口的爆震室中注入推進劑混合物而維持工作。如同一個一級方程式賽車一樣，混合物由一個火花塞點燃，然後，燃氣來不及從燃燒轉向膨脹，就快速產生一個穿過爆震室的爆震波。爆震產生的巨大的爆炸壓力推動排氣從爆震室的開口端排出，從而產生推力。這個由5個爆震管組成的PDE與一個增壓的空氣供給系統直接相連，該系統模擬了Mach 2.5的進氣口壓力和溫度條件。
　　
　　普拉特·惠特尼公司推進計畫經理稱，他們採用一種專利的閥門使PDE的進口與不穩定的燃燒過程分隔開。為與每個爆震管60Hz的工作頻率相匹配，這種類似蝴蝶結的旋轉閥的轉速達18000RPM，並且不斷填加乙烯、氧和壓縮空氣。這個閥門對點火順序進行調節--每個爆震管每隔16.6毫秒點火一次，這意味著該發動機每隔3.5毫秒要點火一次。
　　
　　儘管目前測試的目的是初步運行PDE和驗證PDE的性能，但在這個縮比的實驗型PDE上，每隔0.6毫秒點火一次，已經產生了202.3daN∼266.9daN(500lb∼600lb)的推力。

(Source: US Defense Security Cooperation Agency; issued Sept. 11, 2003)

On 11 September 2003, the Defense Security Cooperation Agency notified Congress of a possible Foreign Military Sale to The United Kingdom of Tomahawk Block IV Land Attack Missiles as well as associated equipment and services. The total value, if all options are exercised, could be as high as $143 million.

The Government of United Kingdom has requested a possible sale of 105 conventionally armed Tomahawk Block IV Land Attack Missiles (TLAM-E), containers, engineering support, test equipment, operational flight test support, communications equipment, technical assistance, personnel training/equipment, spare and repair parts, and other related elements of logistics support. The estimated cost is $143 million.

This proposed sale will contribute to the foreign policy and national security of the United States by improving the military capabilities of the United Kingdom and enhancing weapon system standardization and interoperability of this important NATO ally.

The United Kingdom needs these missiles to replenish missiles expended in support of coalition operations.

The proposed sale will enhance the United Kingdom𠏋 ability to engage in coalition warfare along with the U.S. Navy. The United Kingdom, which already has Tomahawk missiles in its inventory, will have no difficulty absorbing these additional missiles.

The proposed sale of this equipment and support will not affect the basic military balance in the region.

The prime contractor will be Raytheon Missile Systems of Tucson, Arizona. There are no offset agreements proposed in connection with this potential sale.

Implementation of this proposed sale will not require the assignment of any additional U.S. Government or contractor representatives to United Kingdom.

There will be no adverse impact on U.S. defense readiness as a result of this proposed sale.

This notice of a potential sale is required by law; it does not mean that the sale has been concluded.